Pipe transfer apparatus

ABSTRACT

A pipe handling apparatus has a substantially horizontal track and a traveling base member which can travel along the length of the track. An elongate mast is provided. One end of the mast is pivotally affixed to the traveling base member, while a pipe gripper assembly is affixed to the other end of the mast. The pipe gripper includes opposing arcuate jaws which can be selectively opened and closed, as desired, around the outer circumference of a section of pipe or other tubular member. The pipe gripper can be rotated three hundred sixty (360) degrees, and can also be tilted, up or down, relative to such mast.

CROSS REFERENCES TO RELATED APPLICATIONS

NONE

STATEMENTS AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH AND DEVELOPMENT

NONE

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for transferring tubulargoods from a pipe rack v-door to a well bore on a drilling rig. Morespecifically, the present invention relates to an apparatus fortransporting tubular goods from a v-door to a well bore on a drillingrig.

2. Brief Description of the Prior Art

Standard drilling rigs typically comprise a supportive rig floor, aderrick extending vertically above said rig floor, and a traveling blockwhich can be raised and lowered within said derrick. During drillingoperations, such rig equipment is often used to manipulate tubular goods(e.g. drill pipe, tubing, casing and the like) and/or downhole tools ina well bore situated under such derrick. For example, drill bits and/orother equipment are often inserted into a well bore and manipulatedwithin such well bore via tubular drill pipe. Moreover, once a well hasbeen drilled to a desired depth, large diameter and relatively heavypipe called casing is often installed in the well bore and cemented inplace in order to provide structural integrity to the borehole and toisolate downhole formations from one another.

When installing casing, drill pipe or other tubular goods into a wellbore, such pipe is typically installed in a number of sections ofroughly equal length. These pipe sections, often called “joints,” aretypically installed one at a time, and screwed together or otherwisejoined end-to-end to make a roughly continuous string of pipe. In orderto commence the process of inserting pipe in a well bore, a first jointof pipe is lowered into the well bore at the rig floor, and suspended inplace using a set of “slips.” Thereafter, a second joint of pipe isconnected to the top of said first joint, the slips are removed, andboth joints are then lowered into the well bore. The slips are theninstalled at the rig floor, and the process is repeated until thedesired length of pipe has been run into the well bore.

In many instances, pipe and other tubular goods are stored horizontallyon one or more pipe racks in the general vicinity of the rig floor. Assuch pipe/tubular goods are needed for installation in a well bore, thedesired number of joints are transferred from such pipe rack(s) into thedrilling rig derrick; thereafter, such joints are either installeddirectly into the well, or stored vertically within the derrick. Becausemost rig floors and associated derricks are typically elevated abovesuch pipe rack(s), transferring pipe sections between a pipe rack and anelevated rig floor requires careful handling of such pipe. Care must betaken to protect the pipe, as well as the personnel around the rig. Thisis especially true with casing and drill collars, since heavy joints ofcasing and/or drill collars are frequently more difficult to handle thansmaller and lighter pipe, such as drill pipe and tubing.

When pipe is transferred from a pipe storage rack to an elevated rigfloor, one or more joints of pipe are typically loaded on a ramp-likemember, commonly referred to as a “v-door”, which extends between saidpipe rack and said elevated rig floor. Because of the difference inelevation between the pipe rack and rig floor, the v-door is frequentlyinclined at an angle. Once pipe is loaded on to said v-door, the pipe isthereafter lifted, typically one joint at a time, from the v-door into avertical position in the derrick above the elevated rig floor. Once ajoint of pipe is aligned over the well bore (as well as any pipe whichhas already been inserted therein), the suspended section of pipe canthen be connected to the top of the pipe string which is protruding fromthe well bore. Thereafter, the pipe string can be lowered into said wellbore, and the process can be repeated until the desired amount of pipeis inserted into the well.

This method of transferring pipe between a pipe storage rack and aderrick has certain limitations. For example, when a section of pipe islifted from the v-door into the derrick of a rig, the pipe willtypically ride or slide up the v-door until the bottom of said pipereaches the top of said v-door. Once the bottom of said section of pipereaches the top of the v-door, the lower end of the pipe will oftenswing across the rig floor in a dangerous and/or uncontrolled manner.This danger increases when the rig is a floating vessel, such as a drillship or semi-submersible drilling rig, which is susceptible tounpredictable rocking and swaying with wave action.

One common practice is to place a rope or other line across the openingin a derrick where the v-door meets the rig floor. This rope is used asa barrier to hold tension against a section of pipe as it is lifted fromsaid v-door; once the bottom of a section of pipe clears the top of thev-door, the rope provides resistence to prevent the pipe from swingingacross the rig floor in a dangerous or uncontrolled manner. In mostcases, at least one worker will hold on to one end of said rope. Oncethe bottom of a section of pipe clears the top of the v-door, the workercan gradually let out slack in the rope in order to guide the pipesection in the direction of the well bore in a controlled manner. Thispractice is labor intensive, in that at least one worker is required tomaintain tension in the rope and guide movement of said pipe section.This practice is also dangerous, because one or more workers mustfrequently be stationed in awkward or precarious positions.

It can be seen that it would be desirable to be able to grip a sectionof pipe positioned on a drilling rig v-door, move same into verticalorientation over a well bore to permit insertion of the subject pipe insuch well bore. Numerous devices have been proposed to assist in themovement of tubular members between a pipe storage rack and an elevatedrig floor. However, such devices generally do not address problemsassociated with moving pipe from a rig v-door to the well bore within aderrick. Further, existing pipe handling devices are generally complexin construction, designed for use with a particular type or style ofdrilling rig, and not easily transported from one drilling rig toanother. To this end, a need exists for an improved pipe transfer devicewhich is simple in construction, easy to transport and operate, andwhich is adapted to be used with a variety of different types ofdrilling rigs.

BRIEF DESCRIPTION OF THE PRESENT INVENTION

An object of the present invention is to provide a pipe transferapparatus for transferring pipe between: (1) a drilling rig v-door; and(2) a vertical position over a well bore. A further object of thepresent invention is to allow movement of pipe sections between a v-doorand a drilling rig derrick, such that said pipe sections can be advancedinto a well bore for ultimate use in the drilling process, or asotherwise desired. It is to be appreciated that use of the term “pipe”herein encompasses any elongate element or tubular good which can beinserted into, or otherwise used within, a well bore.

The present invention can be easily transported and rapidly installed ona standard drilling rig without substantial alteration of the rig.Moreover, the present invention occupies a minimum amount of space, anddoes not interfere with other operations performed on a rig.

The apparatus of the present invention comprises a substantiallyhorizontal track having two ends, said track being situated on, or ingeneral proximity to, the rig floor of a drilling rig. One terminus ofsaid track is located at or near the opening of the well bore, while theother terminus of said track extends near the upper edge of the v-doorwhere said v-door meets the rig floor. A traveling base member, slidablydisposed on said track, can move along the length of said track. In thepreferred embodiment, said traveling base member is a platform having asubstantially planar upper surface. A means is provided for advancingsaid base member along the length of said track. In the preferredembodiment, said means for advancing said base member along the lengthof said track is a ball reverser. Although said ball reverser can bepowered using any number of different power sources, in the preferredembodiment hydraulic power is used for this purpose. However, it is tobe understood that said ball reverser can be pneumatically orelectrically powered, for example.

An elongate mast is provided. One end of said mast is pivotally affixedto said traveling base member. Said mast can pivot about a horizontalaxis which runs generally perpendicular to the longitudinal axis of saidsubstantially horizontal track. Said mast can also be rotated threehundred sixty (360°) degrees about a vertical axis passing through saidbase member. In the preferred embodiment of the present invention, saidmast is rotated by a slew drive. Although said slew drive can be poweredusing any number of different power sources, in the preferred embodimenthydraulic power is used for this purpose. However, it is to beunderstood that said slew drive can be pneumatically or electricallypowered.

A pipe gripper is affixed to the distal end of said mast. In thepreferred embodiment of the invention, said pipe gripper includesopposing arcuate jaws, which can be selectively opened and closed, asdesired, around the outer circumference of a section of pipe or othertubular member. Said pipe gripper can be rotated three hundred sixty(360°) degrees by rotating said mast about a vertical axis passingthrough said traveling base member using said slew drive. Further, saidpipe gripper can also be tilted, up or down, relative to said mast. Inthe preferred embodiment, said pipe gripper can be tilted relative tosaid mast using a cylinder assembly. Although said cylinder assembly canbe powered using any number of different power sources, in the preferredembodiment said cylinders are powered using hydraulic power.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a fragmentary side view of a drilling rig.

FIG. 2 depicts a side view of the pipe transfer apparatus of the presentinvention with the mast in a reclined position.

FIG. 3 depicts a side view of the pipe transfer apparatus of the presentinvention with the mast in an upright vertical position.

FIG. 4 depicts the pipe gripper of the present invention in an openposition.

FIG. 5 depicts the pipe gripper of the present invention in a closedposition.

FIG. 6 depicts an overhead plan view of the pipe transfer apparatus ofthe present invention.

FIG. 7 depicts a partially exploded side view of the ball reverser ofthe present invention.

FIG. 8 depicts an end view of the pipe transfer apparatus of the presentinvention.

FIG. 9 depicts a side view of the pipe transfer apparatus of the presentinvention with the pipe gripper in a tilted position.

FIG. 10 depicts a side view of the pipe transfer apparatus of thepresent invention with the pipe gripper in a tilted position and themast leaning at an angle from vertical.

FIG. 11 depicts a side view of the pipe transfer apparatus of thepresent invention with a section of pipe received within the pipegripper.

FIG. 12 depicts an overhead sequential view of the pipe transferapparatus of the present invention transferring a section of pipe.

FIG. 13 depicts an overhead sequential view of the pipe transferapparatus of the present invention being repositioned to receive asection of pipe.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

FIG. 1 depicts a fragmentary side view of a drilling rig 100. Drillingrig 100 comprises derrick 101 which extends vertically oversubstantially horizontal rig floor 102. Pipe section 103 is partiallyinstalled in well bore 104, and suspended in place within such well boreusing lower slips 105, so that upper end 103 a of pipe section 103partially protrudes from well bore 104 and extends above rig floor 102.Although not specifically depicted in FIG. 1, it is to be understoodthat well bore 104 can extend a desired length into the surface of theearth. Furthermore, although only pipe section 103 is shown as beinginstalled in well bore 104, it is to be understood that one or moreadditional sections of pipe can be connected below section 103, therebyforming an elongate pipe string which can extend a significant distanceinto the earth via well bore 104. Pipe section 106 is suspended fromelevators 107 within derrick 101 above well bore 104 prior to beingthreadably connected to pipe section 103.

V-door 108 extends from pipe rack 109 to rig floor 102 which is elevatedabove said pipe rack 109. Said v-door 108 essentially forms an inclinedramp between pipe rack 109 and rig floor 102. Pipe section 110 ispositioned on said v-door in advance of being lifted into derrick 101.Because FIG. 1 is for illustration purposes, it is to be understood thatmultiple sections of pipe could be loaded on to v-door 108 at any giventime, and individual sections of pipe could thereafter be lifted fromsaid v-door 108 and into derrick 101 as desired. Furthermore, althoughpipe sections 103, 106 and 110 are depicted as being relatively smalldiameter pipe (such as drill pipe or production tubing), it is to beunderstood that such pipe could also be large diameter pipe, such aswell casing and the like.

One end of a cable or other line is typically attached to upper end 110a of pipe section 110, while the other end of said cable or other linecan be attached to movable elevators 107 or, alternatively, a hoistsituated within derrick 101. As pipe section 110 is lifted using saidcable or line, upper end 110 a of pipe section 110 is pulled upward intoderrick 101, while the remainder of said pipe section 110 slides upv-door 108 toward rig floor 102. As pipe section 110 continues to belifted, eventually bottom 110 b of pipe section 110 will reach the topof v-door 108 and the upper surface of rig floor 102.

A common practice utilized in the oil and gas industry is to secure arope or other line horizontally across the opening in derrick 101 ashort distance above the area where v-door 108 meets rig floor 102 andgenerally perpendicular to the longitudinal axis of pipe section 110. Aspipe section 110 is lifted into derrick 101, said pipe section willessentially ride up v-door 108 and slide against saidhorizontally-stretched rope. As pipe section 110 continues to ride upv-door 108, eventually bottom 110 b of pipe section 110 will clear theupper surface of v-door 108 and rig floor 102. The aforementioned rope,which is typically held in tension across the opening in derrick 101 bya roughneck or other worker, provides resistance against pipe section110 and acts to prevent end 110 b of pipe section 110 from swingingfreely across rig floor 102. Thereafter, a worker holding on to saidrope will typically gradually reduce the tension in said rope, so thatbottom 110 b of pipe section 110 can be guided across rig floor 102 in acontrolled manner. Thereafter, hanging pipe section 110 can be placedinto alignment with pipe section 103 which partially protrudes from wellbore 104.

The present invention eliminates the need for such a rope and thedangers that accompany the aforementioned prior art practice describedherein. The pipe transfer apparatus of the present invention can gripand secure a section of pipe which is being lifted from a v-door into aderrick in order to prevent the base of said section of pipe fromswinging across a rig floor in a dangerous or uncontrolled manner.Further, the present invention eliminates the manpower requirements andsafety concerns associated with existing methods of using a rope orother line to control the movement of pipe across a rig floor asdescribed above.

The apparatus of the present invention comprises a substantially linearhorizontal track having two (2) ends, wherein said track is situated on,or in general proximity to, the rig floor of a drilling rig. Oneterminus of said track is located at or near a well bore such as wellbore 104 in FIG. 1, while the other terminus of said track extends tothe upper edge of a v-door such as v-door 108 in FIG. 1. A travelingbase member is slidably disposed on said track. In the preferredembodiment, said traveling base member is a platform having asubstantially planar upper surface, with a means for advancing said basemember substantially along the length of said track.

FIG. 2 depicts a side view of the pipe transfer apparatus 200 of thepresent invention. Said pipe transfer apparatus comprises substantiallyhorizontal track member 201. Although said track member 201 can take anynumber of sizes and/or shapes, in the preferred embodiment, said trackmember has lower base 201 a and upper rails 201 b. Traveling base member202 is slidably mounted to upper rails 201 b of track member 201. Slewdrive base 203 is affixed to the upper surface of traveling base member202, while mounting bracket 204 is in turn mounted to the upper surfaceof said slew drive base 203. In the preferred embodiment, said mountingbracket 204 is semi-circular in shape, with a curved upper surface. Saidmounting bracket 204 also forms a central channel. Although said centralchannel is not visible in FIG. 2, said channel is oriented substantiallyparallel to the longitudinal axis of substantially horizontal trackmember 201 in FIG. 2.

Elongate mast 205 is pivotally mounted at one end within the centralchannel of mounting bracket 204 using pivot pin 206, thereby allowingelongate mast 205 to pivot within the central channel of mountingbracket 204 about a horizontal axis passing through pivot pin 206.Mounting bracket 204 and, thus, elongate mast 205, can also be rotatedabout a vertical axis passing through slew drive base 203; a slew drive(not shown in FIG. 2) connected to said slew drive base 203 powers suchrotation about a vertical axis. Elongate mast 205 can be locked in placein a reclined position within the central channel of mounting bracket204 using bolt 217 which can be installed through aligned bores inmounting bracket 204 and elongate mast 205. Alternatively, said elongatemast 205 can be locked into an upright, vertical position using bolt218, or a substantially upright tilted position using bolt 219; ineither instance, said bolts can be inserted through aligned bores inmounting bracket 204 and elongate mast 205. In the preferred embodiment,bolts 217, 218 and 219 can be locked in place in aligned horizontalbores extending through mounting bracket 204 and elongate mast 205.

Pipe gripper 300 is affixed to the distal end of said elongate mast 205.In the preferred embodiment of the invention, said pipe gripper 300comprises opposing arcuate jaws, which can be selectively opened andclosed around a section of pipe, as desired. Said opposing arcuate jawscan be closed, for example, around the outer circumference of a sectionof pipe or other tubular member. Said pipe gripper can also be tilted upand down relative to said mast.

In the preferred embodiment, pipe gripper mounting bracket 207 islocated at or near the distal end of elongate mast 205. Pipe gripperassembly 300 is pivotally mounted to said gripper mounting bracket 207using pivot pin 208, thereby permitting said pipe gripper assembly 300to pivot about a horizontal axis passing through said pivot pin 208.

Pivoting of said pipe gripper assembly 300 about said horizontal axispassing through pivot pin 208 is powered by hydraulic cylinder 209. Oneend of hydraulic cylinder 209 is anchored to elongate mast 205 usinganchor bracket 211 and anchor pin 212. Hydraulic cylinder 209 furtherincludes piston rod 210, depicted in the retracted position in FIG. 3.The outer end of piston rod 210 is connected to mounting bracket 301 ofpipe gripper assembly 300 using anchor pin 213. As piston rod 210 ofhydraulic cylinder 209 strokes, pipe gripper assembly 300 pivots aboutpivot pin 208, and can tilt up or down about a horizontal axis passingthrough said pivot pin 208, as desired. Although not visible in FIG. 2,in the preferred embodiment, the aforementioned mechanism for tiltingpipe gripper assembly 300 comprises side-by-side tandem hydrauliccylinders 209.

FIG. 3 depicts a side view of the pipe transfer apparatus of the presentinvention with elongate mast 205 in an upright, vertical position. Inthis position, said elongate mast 205 pivots about pivot pin 206 and islifted upward within the central channel of mounting bracket 204. Whensaid elongate mast is oriented vertically within said central channel ofmounting bracket 204, it can be locked in place using bolt 218. Pipegripper assembly 300 can be rotated three hundred sixty (360°) degreesabout a vertical axis passing through elongate mast 205 via rotation ofelongate mast 205 using a slew drive (not visible in FIG. 3) connectedto slew drive base 203.

Pipe gripper mounting bracket 207 is situated near the distal (upper)end of elongate mast 205. Pipe gripper assembly 300 is pivotally mountedto said pipe gripper mounting bracket 207 via pivot pin 208. One end ofhydraulic cylinder 209 is anchored to elongate mast 205 using anchorbracket 211 and anchor pin 212. The outer end of retracted piston rod210 is connected to mounting bracket 301 of pipe gripper assembly 300using anchor pin 213.

FIG. 4 depicts a perspective view of pipe gripper assembly 300 of thepresent invention in a substantially open position. Pipe gripper 300 iscomprised of opposing arcuate jaws 302 a and 302 b. Said opposingarcuate jaws 302 a and 302 b are pivotally attached to back member 303of pipe gripper assembly 300 using pivot pins 304 a and 304 b, and canswing about said pivot pins 304 a and 304 b to permit opening andclosing of pipe gripper assembly 300. In the preferred embodiment,opposing arcuate jaws 302 a and 302 b operate in synchronized fashion,such that said opposing arcuate jaws 302 a and 302 b open and closetogether.

Hydraulic cylinder 305, which is connected to and supplied hydraulicfluid by hydraulic lines 311, powers the synchronized opening andclosing of opposing arcuate jaws 302 a and 302 b. Hydraulic cylinder 305has piston rod 306, which can be actuated to an extended or retractedposition. One end of hydraulic cylinder 305 is anchored to extensionfingers 309 using anchor rod 310. Similarly, piston rod 306 is anchoredto extension fingers 307 using anchor rod 308. By actuating hydrauliccylinder 305, and thereby causing piston rod 306 to stroke in and out,opposing arcuate jaws 302 a and 302 b can be selectively opened andclosed by pivoting about pivot pins 304 a and 304 b, respectively.

FIG. 5 depicts a perspective view of pipe gripper assembly 300 in asubstantially closed position. Opposing arcuate jaws 302 a and 302 b aredepicted as gripping a section of cylindrical pipe, such as a joint oflarge diameter casing 120, around the outer peripheral surface of saidpipe. For illustration purposes, said cylindrical pipe can be identicalto pipe section 110 in FIG. 1, or a larger diameter pipe section such aspipe joint 120 shown in outline in FIG. 5. As piston rod 306 extendsrelative to hydraulic cylinder 305, opposing arcuate jaws 302 a and 302b pivot about pivot pins 304 a and 304 b, respectively, thereby closingtogether in synchronized manner and gripping around the outer peripheralsurface of casing section 120, thus gripping and securing said pipesection 120 within opposing arcuate jaws 302 a and 302 b. Said opposingarcuate jaws 302 a and 302 b can be opened by pivoting of each of saidarcuate jaws about their respective pivot pins, 304 a and 304 b.

FIG. 6 depicts an overhead plan view of the pipe transfer apparatus ofthe present invention. Substantially horizontal track member 201 hastandem upper rails 201 b; in the preferred embodiment of the presentinvention, said upper rails 201 b are oriented parallel to one another,thereby defining central channel 240 between said upper rails 201 b.Traveling base member 202 is slidably mounted to said tandem upper rails201 b of track member 201, and can move substantially along the lengthof said track member 201. Bearings 214 reduce friction between saidtraveling base member 202 and upper rails 201 b of track member 201.Linear movement of said traveling base member 202 along track member 201is powered by ball reverser 215. Said ball reverser is rotatablyreceived at one end of track member 201 in flange bearing 215 a and atthe other end of track member 201 in flange bearing 215 b. In thepreferred embodiment, said ball reverser is hydraulically powered;however, it should be noted that other power sources could be utilizedfor this purpose.

Elongate mast 205 is shown in FIG. 6 in the upright position. When insuch a position, elongate mast 205 can be rotated about its centrallongitudinal axis by rotation of slew drive base 203. Such rotation ofslew drive 203 and, thus, elongate mast 205, is powered by slew drive216. In this manner, pipe gripper assembly 300, which is attached to theupper end of elongate mast 205, can be rotated three hundred sixty(360°) degrees about a vertical axis passing through said elongate mast205. Although said elongate mast 205 is shown in the upright verticalposition in FIG. 6, said mast can be tilted from vertical by pivotingsaid mast 205 about pivot pin 206 within the central channel formed bymounting bracket 204. Said elongate mast 205 can also be locked in avertical position using bolt 218 (not visible in FIG. 6).

FIG. 7 depicts ball reverser 215 of the present invention. Ball reverser215 comprises central shaft 230 having cross-oriented grooves 231 formedalong the surface of central shaft 230. Central shaft 230 is rotatablyreceived within flange bearing 215 a at one end, and flange bearing 215b at the other end. Motor 232 supplies torque to central shaft 230 viadrive mechanism 233, causing said central shaft 230 to rotate withinflange bearings 215 a and 215 b. Traveling collar 234 is movably mountedon central shaft 230. As central shaft 230 rotates about itslongitudinal axis, traveling collar 234 is directed by grooves 231 andmoves substantially along the length of said central shaft 230.Moreover, because traveling base member 202 is connected to travelingcollar 234, operation of ball reverser 215 causes said traveling basemember 202 to move along the length of substantially horizontal trackmember 201.

FIG. 8 depicts an end view of the pipe transfer apparatus of the presentinvention. Substantially horizontal track member 201 has tandem upperrails 201 b which are aligned parallel to one another, thereby definingcentral channel 240 between said tandem upper rails 201 b. Travelingbase member 202 is slidably mounted to said tandem upper rails 201 b oftrack member 201, and can move substantially along the length of saidtrack member 201. Bearings 214 reduce friction between said travelingbase member 202 and upper rails 201 b of track member 201. In thepreferred embodiment, roller bearings 220 are also provided to reducethe friction between said traveling base member 202 and upper rails 201b of track member 201. Linear movement of said traveling base member 202along track member 201 is powered by ball reverser 215 (not shown inFIG. 8) which extends substantially along the length of track member201. Said ball reverser is rotatably received at one end of track member201 in flange bearing 215 a.

Elongate mast 205 is shown in the upright position. Said elongate mast205, which is received within the central channel formed by mountingbracket 204, can be rotated about its central longitudinal axis byrotation of slew drive base 203, which is powered by slew drive 216. Inthis manner, pipe gripper assembly 300, which is attached to the upperend of elongate mast 205, can be rotated about a vertical axis passingthrough said elongate mast 205. Although said elongate mast 205 is shownin the upright vertical position, said mast can be tilted from verticalby pivoting about pivot pin 206. Further, said elongate mast 205 can belocked in an upright vertical position using bolt 218.

Still referring to FIG. 8, pipe gripper assembly 300 can be titled abouta horizontal axis using tandem hydraulic cylinders 209. One end of saidtandem hydraulic cylinders 209 is anchored to elongate mast 205 usinganchor brackets 211. Hydraulic cylinders 209 further include piston rods210 (which are depicted in the retracted position in FIG. 8). The outerend of said piston rods 210 is pinned to mounting brackets 301 of pipegripper assembly 300. As said piston rods 210 extend, pipe gripperassembly 300 can be tilted about a horizontal axis passing through pivotpin 208.

FIG. 9 depicts a side view of the pipe transfer apparatus of the presentinvention with elongate mast 205 in an upright position and pipe gripperassembly 300 in a tilted position. Traveling base member is shown atapproximately the mid-point of substantially horizontal track member201. Elongate mast 205 is oriented in a substantially vertical positionwithin the central channel of mounting bracket 204; that is,perpendicular to track member 201. If desired, elongate mast 205 can besecured in a substantially vertical position using bolt 218. Piston rod210 is extended from hydraulic cylinder 209, thereby causing pipegripper 300 to tilt about a horizontal axis passing through pivot pin208. It is to be observed that the greater the stroke of piston 210, themore that pipe gripper 300 will tilt and, consequently, the greaterangle “x” in FIG. 9 will be.

FIG. 10 depicts a side view of the pipe transfer apparatus of thepresent invention. Elongate mast 205 is depicted in a position which istilted from vertical. As said elongate mast 205 pivots about pivot pin206 within the central channel of mounting bracket 204, said mast cantilt from vertical and, if desired, be locked in this position usingbolt 219. It is to be observed that the more that elongate mast 205 istilted from vertical, the greater angle “y” in FIG. 10 will be.

FIG. 11 depicts the pipe transfer apparatus of the present invention insubstantially the same position as depicted in FIG. 10. Elongate mast205 is tilted from vertical, and locked in place within the centralchannel of mounting bracket 204 using bolt 219. Piston rod 210 isextended from hydraulic cylinder 209, and pipe gripper apparatus 300 isitself tilted upward relative to said elongate mast 205. Opposingarcuate jaws 302 a and 302 b of pipe gripper assembly 300 are in asubstantially closed position around the outer circumference ofcylindrical pipe section 110.

It is noted that opposing arcuate jaws 302 a and 302 b are notcompletely closed about the outer surface of pipe section 110. Whilesaid pipe section may lean to one side or the other, there is generallycircumferential clearance around much of the outer surface of said pipesection within said opposing arcuate jaws 302 a and 302 b. In this way,pipe gripper assembly 300 can grab and/or facilitate handling of saidpipe section. However, because of such clearance within jaws 302 a and302 b, said pipe section can ideally be raised and lowered, as well asrotated, even when said opposing arcuate jaws 302 a and 302 b are closedaround said pipe section 110. As described above, elongate mast 205 andpipe gripper assembly 300 can be tilted, as desired, to facilitatehandling of pipe section 110, particularly when said pipe section islocated on an inclined v-door.

FIG. 12 depicts an overhead sequential view of the pipe transferapparatus of the present invention transferring a section of pipe. Inposition “a”, opposing arcuate jaws 302 a and 302 b of pipe gripper 300are shown in the substantially open position, and said pipe section 110is received within said jaws. In position “b”, said opposing arcuatejaws 302 a and 302 b are closed around the outer surface of pipe section110. Elongate mast 205, depicted in an upright, vertical position, isrotated 90° using slew drive 216. In positions “c” and “d”, travelingbase 202 travels along the length of substantially horizontal trackmember 201 (not shown in FIG. 12). Said traveling base 202 continuesmoving along to substantially horizontal track member 201 until itreaches the desired position, which is typically the terminus of saidsubstantially horizontal track member 201. In this position, position“e” on FIG. 12, elongate mast is rotated an additional 90° using slewdrive 216. In position “e”, the orientation of pipe gripper 300 is 180°from its orientation in position “a”. Opposing arcuate jaws 302 a and302 b of pipe gripper assembly 300 are then opened, allowing pipesection 110 to be easily removed from said pipe gripper assembly.

FIG. 13 depicts an overhead sequential view of the pipe transferapparatus of the present invention being reset to receive another pipesection, such as pipe section 110. In position “e”, elongate mast 205 isin an upright vertical position and opposing arcuate jaws 302 a and 302b of pipe gripper assembly 300 are open. Pipe section 110 has beenremoved from pipe gripper assembly 300. In position “f”, said elongatemast 205 rotates 900 and traveling base 202 slides along the length ofsubstantially horizontal track member 201 (not shown in FIG. 13). Inposition “f”, said traveling base member is shown at approximately themid-point of said horizontal track member. In position “g”, saidtraveling base 202 has continued along the length of said horizontaltrack member, and elongate mast 205 has rotated an additional 90°,thereby presenting pipe gripper assembly 300 in the open position toreceive another section of pipe for transfer.

In operation, the pipe transfer apparatus of the present invention canbe installed on a drilling rig or other similar location. Specifically,the substantially linear horizontal track is situated on, or in generalproximity to, the rig floor of a drilling rig. One end of said track islocated at or near a well bore, while the other end of said track islocated at or near the upper end of a v-door.

The pipe gripper assembly of the present invention is positioned at ornear the upper end of said v-door, typically in a fully open position(see position “g” in FIG. 13). As a section of pipe is lifted off ofsaid v-door, and into the derrick of said drilling rig, said pipesection is directed into said open pipe gripper assembly (see position“a” in FIG. 12). After said pipe section has cleared the top of saidv-door, said pipe gripper assembly is closed around said section ofpipe. Thereafter, pipe gripper assembly swivels 900 (see position “b” inFIG. 12), and travels along the length of the substantially linearhorizontal track (see positions “c” and “d” in FIG. 12).

After the pipe gripper assembly reaches the end of said track and is ator near the well bore, the pipe gripper assembly is rotated 90° andopened (see position “e” in FIG. 12). Thereafter, the pipe section canbe removed from the pipe gripper assembly and connected to a string ofpipe suspended within the well bore. Said pipe gripper assembly can berotated and returned to its original position (see positions “f” and “g”in FIG. 13). The process can be repeated until the desired amount ofpipe has been installed in said well bore.

Although the apparatus of the present invention has been depicted in aparticular form constituting a preferred embodiment, it will beunderstood that various changes and modifications in the illustrated anddescribed structure can be effected without departure from the basicprinciples which underlie the invention. Changes and innovations of thistype are deemed to be circumscribed by the spirit and scope of theinvention except as such spirit and scope may be necessarily limited bythe appended claims, or reasonable equivalents thereof.

1. An apparatus for handling pipe on a drilling rig comprising: a. asubstantially linear track having a first end and a second end; and b.means for gripping pipe which can be selectively positioned between thefirst and second ends of said track.
 2. The apparatus of claim 1,wherein said track is situated on the rig floor of a drilling rig. 3.The apparatus of claim 2, wherein the first end of said track is locatednear a wellbore, and the second end of said track is positioned near theupper end of a v-door.
 4. An apparatus for handling pipe on a drillingrig comprising: a. a substantially linear track having a first end and asecond end; b. a platform slidably received on said track, wherein saidplatform can travel between the first and second ends of said track; andc. means for gripping pipe.
 5. The apparatus of claim 4, wherein saidmeans for gripping pipe further comprises: a. a back member; b. a firstarcuate jaw pivotally attached to said back member; and c. a secondarcuate jaw pivotally attached to said back member, wherein said firstand second arcuate jaw members oppose each other.